Wafer-level testing apparatus and method

ABSTRACT

A semiconductor component configured for wafer-level testing includes a semiconductor die having at least one die contact electrically exposed for coupling with a redistribution circuit that electrically couples at least one die contact to an extended contact such as a bumped contact. The component further includes a bus conductor that traverses at least a portion of the die and electrically mates with corresponding bus conductors on other similarly prepared components on the wafer. Functional and nonfunctional dice are identified on the wafer and the nonfunctional dice are isolated from the wafer-level testing grid. Following test, dice may be subsequently tested or moved to singulation wherein the die-to-die interconnection is interrupted, allowing wafer-level tested components to be conventionally assembled. A wafer may be retrofit with the wafer-level redistribution circuit for facilitating wafer-level testing without requiring customization of test fixtures or software for avoiding testing of nonfunctional dice.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of application Ser. No. 10/347,027,filed Jan. 17, 2003 now U.S. Pat. No. 6,744,067, issued Jun. 1, 2004.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to semiconductor testing and,more particularly, to wafer-level burn-in and testing of components onsemiconductor wafers.

2. State of the Art

It is advantageous in semiconductor processing to detect and screen outdefective integrated circuits (ICs) as early as possible in themanufacturing process. It is appreciated that many manufactured ICs failwithin the first few months or weeks of use due to processing defects.Such a defect profile is commonly known as “infant mortality” and isclearly very undesirable and unacceptable for a typical IC customer. Todiscover those circuits that are susceptible to infant mortality,manufacturing processes have included high temperature testing of ICsfor extended periods of time before shipping products to a customer.

In a typical semiconductor manufacturing process, a multiplicity ofintegrated circuits is formed as individual dice on a semiconductorwafer. Such a multiplicity of integrated circuits may number in the tensto hundreds, or even thousands (such as in a 300 mm wafer) of individualdice which are generally repeated across the wafer in a two-dimensionalarray. Once the dice are formed on a semiconductor wafer, the dice arethen tested to determine which dice are functional with such adetermination performed, generally, by probing each die individually.The probing of individual dice is performed using very costly probeequipment while the die is still in wafer form. Presently availableprobe equipment contacts each bonding pad on an individual die with aseparate probe. A typical probe test requires that each die be probed inorder to determine the correct and acceptable functionality of each die.However, due to the expensive nature of the probing test equipment,reliability testing (i.e., testing an individual circuit over time) isgenerally not performed.

It should be apparent that the purpose of wafer-level probing is todetermine as early as possible in the manufacturing process thefunctional nature of each individual die. The earlier a defective die isdetected, the fewer subsequent processing steps are performed on thedefective die, which results in a reduction of costs associated withindividual wafer processing. Upon the completion of functional probetesting, those defective dice are noted and subsequent manufacturingprocesses are not exerted.

Upon the identification of functional and nonfunctional dice, the diceare then separated or singulated by way of a dicing process. Followingsingulation, functional dice are packaged into integrated circuitpackages or undergo further processing which allows the dice to beassembled as part of a higher-level assembly, which itself may bepackaged. Once the dice have been packaged or prepared for packagingwithin a higher assembly, thorough electrical testing is performed todetermine whether each packaged integrated circuit properly performs thefunctionality for which it was designed. Upon successful packagetesting, integrated circuits may be sold or integrated into higherassemblies.

An additional common manufacturing process includes subjecting thepackaged integrated circuits to a form of reliability testing calledburn-in. Burn-in testing involves testing an IC for an extended periodof time at elevated operational temperatures. During the burn-in test,additional infant mortality failures manifest themselves and are furtherculled from the original multiplicity of manufactured dice. Burn-intesting may also utilize reduced temperature testing and may furtherinclude repetitive cycling of the packaged integrated circuit in anattempt to fatigue and fail frail ICs. Typical burn-in testing hasutilized a concept of burning in packaged dice which have lessfine-pitched inputs and outputs. Furthermore, the inputs and outputs ofthe packaged integrated circuit provide a more economical testingapproach rather than the very fine-pitched probing mechanism used forindividual die probing.

Conventional economical and high-volume approaches for burn-in testingof dice at a wafer level have required expensive and customized probingequipment. Therefore, there exists a need for a wafer-level testingmethodology that does not require special processing or elaborate probetesting of individual integrated circuits at a wafer-level burn-instage.

BRIEF SUMMARY OF THE INVENTION

In accordance with the present invention, semiconductor componentsconfigured for wafer-level testing, semiconductor wafers fabricated forwafer-level testing and methods for fabricating wafer-level testabledice are provided.

A semiconductor component includes a semiconductor die that performsspecific functions and contains circuitry for performing those specificfunctions. The semiconductor die is fabricated according to conventionalfabrication processes with each die including a defined number of diecontacts that are electrically exposed for subsequent interconnectionwith other electronic components. One embodiment of the presentinvention contemplates busing contacts of interest together from atleast one die to at least one other die for wafer-level testing.

In addition to at least one die, the semiconductor component includes aredistribution circuit for electrically coupling the die contact on thesemiconductor die to a redistributed contact such as a bumped contact.The redistribution circuit is formed on top of the conventionallyprocessed semiconductor wafer with the conductive trace electricallycoupling with the die contact. The conductive trace is preferably formedby patterning a conductor such as aluminum onto the exposed wafersurface. The redistribution circuit may or may not physically containthe solder ball portion of the bumped contact; however, in one topology,the redistribution circuit's patterned conductor may serve as anisolation region for forming an open circuit therein when a die isdetermined to be nonfunctional.

The semiconductor component configured for wafer-level testing alsoincludes a bus conductor for providing a die-to-die routing of aspecific signal. The specific signal is then available to test equipmentat the wafer level for providing inputs or for receiving outputs. Thebus conductor traverses at least a portion of the semiconductor die forproviding the die-to-die interconnection or busing function. The busconductor may also be formed from patterned conductors and is preferablyformed in the same processes that form the patterned conductor used inthe redistribution layer.

The bus conductor is also in electrical communication with theredistribution circuit to receive or provide a signal to the die contactof the specific die. To facilitate the electrical connection between thebus conductor and the redistribution circuit, various embodiments arepresented. One embodiment contemplates the intersection of the busconductor and the redistribution circuit, while another embodiment formsan additional conductor for providing the electrical coupling. As withthe bus conductor, this conductor may be formed in a unitary processwith both the redistribution circuit and the bus conductor.

While not all dice on a wafer may be functional and cooperative forwafer-level testing, the present invention contemplates probe testingthe dice on a wafer that have been manufactured with the wafer-leveltestable circuitry of the present invention. Functional andnonfunctional dice are identified with location information stored thatis used in a follow-up process that isolates the nonfunctional dice fromthe networked configuration of the dice on the wafer. In order to removeor isolate the nonfunctional dice from the wafer-level test grid, one ormore die contacts from the nonfunctional wafer are isolated from therespective bus conductor. The isolation process may take the form ofremoving any outer passivation layer that exists over the redistributioncircuit region or the conductor that connects the redistribution circuitto the bus conductor to expose the underlying conductive trace. Removalof any outer passivation layer may be performed by laser ablation or byan etching process or otherwise. Additionally, the conductive trace isinterrupted to form an electrical open circuit between the die contactand the bus conductor. The conductive trace may also be laser ablated oretched or otherwise removed according to known processing methods.

Following the busing together of a plurality of dice on a wafer followedby the isolation of nonfunctional dice from the array of functionaldice, the wafer is in a wafer-level testable configuration. Wafertesting may be performed which may include burn-in testing withoutrequiring intricate and otherwise expensive test equipment. Variousmethods for manufacturing wafer-level testable semiconductor devices aswell as methods for retrofitting existing wafer designs for wafer-leveltesting are also encompassed by the present invention.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

In the drawings, which illustrate what is currently considered to be thebest mode for carrying out the invention:

FIG. 1 is a bottom view of a semiconductor package having externalbumped contacts in accordance with an embodiment of the presentinvention;

FIG. 1A is an enlarged cross-sectional view taken along the section line1A—1A of FIG. 1 illustrating a redistribution circuit as well as awafer-level test interconnect, in accordance with an embodiment of thepresent invention;

FIG. 2 is a plan schematic view of a wafer of semiconductor componentsincluding wafer-level test interconnects, in accordance with anembodiment of the present invention;

FIG. 3 is also a plan view of a semiconductor wafer illustratingwafer-level test interconnects between adjacent dice thereon, inaccordance with an embodiment of the present invention;

FIG. 4 illustrates various patterned conductors and FIGS. 4A-4C aredetailed views of a wafer-level test interconnect for coupling adjacentdice, in accordance with an embodiment of the present invention;

FIG. 5 is a cross-sectional view of an isolated contact of a defectivedie from the wafer-level test interconnect, in accordance with thepresent invention;

FIGS. 5A-5C are detailed views of isolation regions of a wafer-leveltest interconnect, in accordance with an embodiment of the presentinvention;

FIG. 6 is a flow chart of wafer-level test processing in accordance withan embodiment of the present invention; and

FIG. 7 illustrates an alternative coupling of adjacent dice forperforming wafer-level testing, in accordance with another embodiment ofthe present invention.

DETAILED DESCRIPTION OF THE INVENTION

Semiconductor components, such as bare semiconductor dice, semiconductorpackages, chip scale packages, BGA devices, and semiconductor wafers,may include terminal contacts in the form of bumps. This type ofcomponent is sometimes referred to as a “bumped” component (e.g., bumpeddie, bumped package, bumped wafer).

FIGS. 1 and 1A illustrate a bumped semiconductor component whichcomprises, for example, a “flip chip” configured semiconductor package10. The package 10 includes a semiconductor die 12 and an array ofbumped contacts 14 bonded to a face 16 (circuit side) of the die 12. Thebumped contacts 14 allow the package 10 to be surface mounted to asubstrate having a corresponding pattern of terminal pads thereon, suchas a printed circuit board (PCB). Typically, the bumped contacts 14 aremade of solder, such that the package 10 can be bonded to the substrateusing a solder reflow process. However, conductive bumps of conductiveor conductor-filled epoxy are also conventionally employed. In addition,the bumped contacts 14 can be arranged in a dense array, such as a ballgrid array (BGA) or a fine ball grid array (FBGA), to provide a highinput/output capability for the package 10. Further, the bumped contacts14 may have a spherical, hemispherical, conical, dome, pillar, column,stud or other shape.

The die 12 contained in the package 10 includes a pattern of diecontacts 20 (e.g., bond pads) in electrical communication with thebumped contacts 14. In addition, the die 12 includes internal conductors22 in electrical communication with the die contacts 20 and with variousintegrated circuits formed on the die 12. The die 12 also includes apassivation layer 24 formed on the face 16 of the die 12 and openings 26through the passivation layer 24 to the die contacts 20. Typically, thepassivation layer 24 comprises a glass, such as boro-silicate glass(BSG), phosphosilicate glass (PSG), borophosphosilicate glass (BPSG), anoxide, such as SiO₂, or a polymer, such as polyimide or silicon nitride(SiN).

The die 12 also includes a wafer-level test redistribution circuit 32formed on a surface 34 of the passivation layer 24, which interconnectsthe bumped contacts 14 to the die contacts 20 and further interconnectsat least a portion of die contacts 20 with like contacts on an adjacentlike die for providing a busing or ganging of input/output terminals ofthe like die during wafer-level testing. The wafer-level testredistribution circuit 32 includes a pattern of conductors 36 inelectrical communication with the die contacts 20 and an outerpassivation layer 38 which covers the conductors 36. The conductors 36can have a “fan out” configuration to provide a required pitch andpattern for the bumped contacts 14 as well as die-to-die coupling oflike contacts for wafer-level testing. Redistribution circuit 32 may bemanufactured using deposition, masking and etching steps for exposingdie contacts 20 and depositing patterned conductors 36 in a desiredinterconnection array.

The outer passivation layer 38 of the wafer-level test redistributioncircuit 32 insulates the conductors 36 and helps to locate and confinethe bumped contacts 14. Thus, the outer passivation layer 38 functionsas a solder mask to prevent solder from flowing between the bumpedcontacts 14 during attachment of the bumped contacts 14 and duringsurface mounting of the package 10. The outer passivation layer 38 maycomprise a dielectric material. Suitable materials for the outerpassivation layer 38 include polymers, such as polyimide SiN, glasses,such as BSG, PSG, BPSG, or oxides, such as SiO₂. The outer passivationlayer 38 includes openings 40, and the bumped contacts 14 are locatedwithin the openings 40 and bonded to the conductors 36.

FIG. 2 schematically illustrates a processed wafer configured forwafer-level testing, in accordance with an embodiment of the presentinvention. A wafer 52 is illustrated as generally being comprised of aplurality of components 50, each of which is in the form of a processeddie having electronic circuitry formed in accordance with the desiredspecific semiconductor device function and further processed with thewafer-level test redistribution circuit as described previously inFIG. 1. A portion of the wafer-level test redistribution circuit isillustrated in FIG. 2 according to the exposed portions, namely, bumpedcontacts 58, which may be individually utilized for probe testing ofindividual dice. Furthermore, the various components 50 of wafer 52 maybe electrically coupled to adjacent dice through an external means, inaccordance with an alternate embodiment, as described below inrelationship to FIG. 7, or through a preferable interconnectionmechanism which provides adjacent interconnection through the use ofpatterned conductors on wafer 52.

FIG. 3 schematically illustrates wafer 51 fabricated in accordance withthe preferred patterned interconnection of adjacent dice through the useof patterned conductors which form a portion of the wafer-level testredistribution circuit as described previously with relation to FIG. 1.FIG. 3 illustrates components 50 being coupled to adjacent others ofcomponents 50 through the use of patterned conductors 54. To simplifythe view of FIG. 3, the bumped contacts 58 of FIG. 2 have not beenillustrated in FIG. 3 but are further detailed with reference to FIG. 4.Referring to FIG. 3, patterned conductors 54 gang or otherwise connectin a bus or parallel format a plurality of components 50 forfacilitating the conduction of input/output signals to each ofcomponents 50 during wafer-level testing. Patterned conductors 54 may befurther combined or, alternatively, multiplexed through bus circuits 56,which may be formed as separate integrated circuit components, orpatterned conductors 54 may alternatively be directly routed to waferterminals 60.

In the case of “legacy” or existing wafer layouts, it is preferable thatpatterned conductors 54 be directly coupled to wafer terminal 60 so asto not require any processing modifications to the electroniccomponentry or layout of wafer 51. As described herein and with respectto existing wafer layouts, the application of a wafer-level testredistribution circuit may be a post-component circuitry fabricationprocess which attaches patterned conductors to existing die contacts forredistribution of the physical and electrical interfaces with thecircuit of die 12 (FIG. 1) for facilitating wafer-level testing.

FIG. 4 is a detailed top view of a wafer-level test redistributioncircuit, in accordance with an embodiment of the present invention. FIG.4 illustrates adjacent components 62 and 64 as interconnected fortesting at a wafer-scale level. Components 62 and 64 are separated bystreet or scribe lane 66 for use in a post wafer-level test segmentationprocess wherein components 62 and 64 are segmented from a unitary waferinto physically separated components. While FIG. 4 depicts adjacentcomponents being coupled in a horizontal manner (with respect to theorientation of FIG. 4), vertical busing for interconnection of adjacentcomponents and even a combination of vertical and horizontal as well asdiagonal interconnections in the plane of the wafer is alsocontemplated. Furthermore, while FIG. 4 illustrates the busing of allcontacts 14, 20 resident on components 62 and 64 a partial busing isalso contemplated wherein only a portion of the contacts 14, 20, andeven as few interconnections as for the busing of power and groundsignals, is also contemplated by the present invention.

FIG. 4 illustrates the coupling of components 62 and 64 through the useof patterned conductors 54, or more specifically bus conductors 68through 74. FIG. 4 further illustrates a redistribution circuit betweendie contacts 20 and bumped contacts 14 and, more specifically, FIGS.4A-4C (specifically) depict various interconnection schemes contemplatedfor coupling the bus conductors to the redistribution circuits.

FIG. 4A depicts one embodiment of a wafer-level test redistributioncircuit 76 which includes a redistribution circuit 78 for facilitatingthe coupling of die contact 20 with an external circuit board orassembly via bumped contact 14. Redistribution circuit 78 includes apatterned conductor 80 for facilitating electrical contact betweenbumped contact 14 and die contact 20. Manufacturing processes of such aredistribution circuit are described above with reference to FIG. 1A.Wafer-level test redistribution circuit 76 further comprises thecoupling of redistribution circuit 78 with bus conductor 68 through theuse of a patterned conductor 82 which provides the electrical couplingof specific inputs and outputs of specific components to bus conductors68 for coupling with other corresponding inputs and outputs of othercomponents on the same wafer, as well as coupling with bus circuits 56or wafer terminals 60 (FIG. 3).

FIG. 4B illustrates another embodiment of a wafer-level testredistribution circuit 84 which includes a redistribution circuit 86used for coupling die contact 20 with an external interface such as aboard or other higher-level assembly. Redistribution circuit 86 includespatterned conductor 88 which electrically couples die contact 20 withbumped contact 14, and is further electrically coupled to bus conductor70 by the intersection of bus conductor 70 with patterned conductor 88.

FIG. 4C depicts yet another embodiment of wafer-level testredistribution circuit 90 which includes a redistribution circuit 92 forcoupling die contact 20 with an external interface such as a board orother higher-level assembly. Redistribution circuit 92 includes apatterned conductor 94 and a bumped contact 14. Patterned conductor 94is coupled to bus conductor 74 by way of a patterned conductor 96 whichis in electrical communication with patterned conductor 94. Whilevarious exemplary interconnection embodiments have been depicted, otherforms of coupling a die contact 20 with a bus conductor are alsocontemplated to be within the scope of the present invention.

FIG. 5 is a cross-sectional view of isolating die contacts of faileddice, in accordance with an embodiment of the present invention. Itshould be recalled that the formation of wafer-level test redistributioncircuit 32 may occur as a post process to the fabrication of theplurality of dice 12 on the wafer. At such a processing point, probetesting has been performed and, therefore, the application of thewafer-level test redistribution circuit 32 results in theinterconnection of all dice and inputs and outputs as designated in thepatterning design for the formation of the patterned conductors.However, it is known that some dice will generally be nonoperational anddefective with the specific defection mechanism generallyuncharacterized and unpredictable. Therefore, following the fabricationof wafer-level test redistribution circuit 32, the wafer, and moreprecisely the individual die, is subjected to probe testing to identifyand discriminate between functional and nonfunctional dice. Because ofthe various failure mechanisms in the nonfunctional dice, those dicemust be isolated from the bus conductors so as to not negatively affectthe ability to perform wafer-level testing or damage test equipment bythe introduction of, for example, short-circuits, excessive capacitance,or other electrically undesirable conditions.

Once the nonfunctional dice have been identified, the patternedconductors connecting die contact 20 with the bus conductors must besevered or otherwise interrupted. FIG. 5 illustrates a severing processwherein outer passivation layer 38 is removed to provide access to thepatterned conductor. It is appreciated that mechanisms for removingouter passivation layer 38 may include photolithographic processes aswell as an illustrated process wherein a laser, such as laser 122,ablates outer passivation layer 38, to expose patterned conductor 36 forsevering in a subsequent process. One such severing process contemplatedwithin the scope of the present invention further utilizes laser 122 tofurther ablate patterned conductor 36, to form an open circuit betweendie contact 20 and bus conductors. Yet another approach for forming anopen circuit in the patterned conductor includes ablating outerpassivation layer 38 using laser 122 and performing an etching processfor removing the underlying patterned conductor to isolate thenonfunctional component from any subsequent wafer-level testing. In thiscurrently preferred approach, no photolithography is required as thepassivation layer 38 acts as a mask for the etching process.

FIG. 5 illustrates the severing of patterned conductor 114 by theforming of an opening 116 through one of the aforementioned approaches.Alternatively, when the redistribution circuit 32 is coupled to a busconductor through the formation of a patterned conductor coupling fromthe bumped contact region toward the bus conductor, conductor 118 may besevered by forming a void 120 through one of the aforementionedprocesses, to form an open circuit in yet another manner between diecontact 20 and the respective bus conductor.

FIGS. 5A-5C correspond to the wafer-level test redistribution circuitembodiments of FIGS. 4A-4C and further illustrate acceptable locationsfor severing or forming an open circuit with which to isolate the diecontact from the bus conductor. In FIG. 5A, formation of an open circuitmay appropriately occur in region 124. Furthermore, in FIG. 5B,isolation may occur through the formation of an open circuit in region126. Similarly, an open circuit in a wafer-level test redistributioncircuit embodiment as depicted in FIG. 5 may occur by forming a severingof the patterned conductor in region 128. It should be appreciated bythose of ordinary skill in the art that a subset of wafer-level testredistribution circuits on a particular die may be severed and form aneffective isolation of the die from the wafer-level test process. Forexample, an acceptable isolation of a nonfunctional die may be made incertain applications by the severing of the power and/or groundinterconnection with the corresponding die contact with any resultingcapacitance on the remaining connected inputs and outputs beingtolerated as acceptable capacitances.

FIG. 6 is a flow chart detailing the steps for performing wafer-leveltest processing, in accordance with an embodiment of the presentinvention. Wafer-level test processing 100 is performed by preparing orprocessing a wafer having discrete components or dice thereon accordingto conventional processing steps 102. Such steps for performingconventional processing are appreciated by those of ordinary skill inthe art and, in accordance with the present invention, include theprocess of making die contacts 20 electrically available for theelectrical coupling of wafer-level test redistribution circuit 32.Subsequent to the formation of a wafer using conventional processingtechniques, a plurality of wafer-level test distribution circuits areformed over the wafer, including the formation of redistributioncircuits 78, 86, and 92 for electrically routing the die contacts out toan interface such as bumped contacts 14. Furthermore, step 104 furtherincludes the formation of patterned conductors such as patternedconductors 82 and 96 of FIGS. 4A and 4C respectively for electricallycoupling die contacts 20 with corresponding bus conductors, or,alternatively, as illustrated in FIG. 4B, bus conductor 70 may intersectredistribution circuit 86 to provide electrical continuity therewith.The present invention contemplates a unitary process for forming (i) theredistribution circuits for coupling die contact 20 with bump contacts14, (ii) the formation of bus conductors 68-74, and (iii) the formationof patterned conductors 82 and 96 for coupling with the bus conductors.

In step 106, the individual dice of the processed wafer then undergoprobe testing of each individual die or groups of dice in order todetermine and segregate operational dice from non-functional dice. Instep 108, the identities of the functional and nonfunctional dice on thewafer-under-test are identified and retained for future processing. Step110 isolates one or more die contacts from bus conductors (see FIG. 5)according to the test results from probe testing in step 106. Thenonfunctional dice are isolated prior to performing wafer-level testingin step 112. Wafer-level testing and the coupling of equipment therewithis well known to those of ordinary skill in the art.

FIG. 7 illustrates an alternate embodiment for coupling the individualcomponents together for wafer-level testing through the use of busingexternal to the wafer. In the present embodiment, the entire wafer isloaded into a fixture 130, the cross-section of which is seen in FIG. 7.In general, the fixture serves to bring a printed circuit board (PCB)132 into precise electrical contact with the bumped contacts on thewafer 134. Direct contact is made from PCB 132 to wafer 134 through aplurality of conductive probe pins 136, one probe pin 136 per bumpedcontact 14 to be bused for wafer-level testing. Therefore, eachcomponent on wafer 134 is independently routed via the probe pins 136and traces of the PCB 132 to connectors 140 which electronically connectthe PCB 132 and, hence, the wafer 134 to the outside world. Outboardtest equipment as is known in the art can be connected to operate thePCB 132 and wafer during test and burn-in. This allows each component tobe tested and allows all the dice on the entire wafer 134 to be testedin parallel.

Because the connection of probe pins with other probe pins is performedexternal to the wafer, the configuration of probe pins 136 remainsconstant for the particular wafer layout regardless of which dice arenonfunctional. The nonfunctional dice are open-circuited from theremaining bused dice by the isolation process as described with respectto FIG. 5. Further, since bus coupling occurs at the bumped contact, theisolation region may be located anywhere along the redistributioncircuit which would result in an open circuit between the bumped contactand the die contact.

The wafer 134 is attached to a carrier frame 142 which may then be matedwith PCB 132. Probe pins 136 are then aligned and brought into contactand a uniform compressing force is exerted across both the PCB 132 andthe wafer 134, thereby maintaining proper contact between them.

While certain exemplary embodiments of the invention have beendescribed, modifications thereto may be made and other embodiments maybe devised without departing from the spirit of the invention and thescope of the appended claims.

1. A method for testing a plurality of semiconductor components,comprising: forming a plurality of dice on a semiconductor wafer, theplurality of dice each including at least one die contact; and formingat least one wafer-level redistribution circuit on each of the pluralityof dice for interconnection with others of the plurality of dice, the atleast one wafer-level redistribution circuit including a redistributioncircuit, and a bus conductor traversing each of the plurality of dicefor electrically coupling with at least another one of the plurality ofdice and at least one conductor for coupling the redistribution circuitto the bus conductor.
 2. The method, as recited in claim 1, furthercomprising forming an outer passivation layer on an exposed face of thesemiconductor wafer covering the redistribution circuit and the busconductor.
 3. The method, as recited in claim 2, further comprisingprobing each of the plurality of dice to determine functional andnonfunctional dice.
 4. The method, as recited in claim 3, furthercomprising storing location information on nonfunctional dice.
 5. Themethod, as recited in claim 4, further comprising isolating the at leastone die contact on each of the nonfunctional dice.
 6. The method, asrecited in claim 5, wherein isolating includes removing a portion of theouter passivation layer over at least one of the redistribution circuitand the bus conductor to form an open circuit between the at least onedie contact and the bus conductor on nonfunctional dice.
 7. The method,as recited in claim 5, wherein isolating includes ablating of at least aportion of the at least one wafer-level redistribution circuit and theouter passivation layer.
 8. The method, as recited in claim 5, whereinisolating includes etching of at least a portion of the at least onewafer-level redistribution circuit and the outer passivation layer.
 9. Amethod for manufacturing wafer-level testable dice, comprising: forminga plurality of dice on a semiconductor wafer, the plurality of dice eachincluding at least one die contact; and forming at least one wafer-levelredistribution circuit on each of the plurality of dice forinterconnection with others of the plurality of dice, the at least onewafer-level redistribution circuit including a redistribution circuit,and a bus conductor traversing each of the plurality of dice forelectrically coupling with at least another one of the plurality of diceand at least one other bus conductor for coupling the redistributioncircuit to the bus conductor.
 10. The method, as recited in claim 9,further comprising isolating at least one of the at least one diecontact on nonfunctional dice of the plurality of dice on thesemiconductor wafer.
 11. The method, as recited in claim 9, furthercomprising probing each of the plurality of dice to determine functionaland nonfunctional dice of the plurality of dice.
 12. A method forfabricating a wafer-level testable semiconductor component, comprising:forming a plurality of dice on a semiconductor wafer, the plurality ofdice each including at least one die contact; forming at least onewafer-level redistribution circuit on each of the plurality of dice forinterconnection with others of the plurality of dice, the at least onewafer-level redistribution circuit including a redistribution circuit,and a bus conductor traversing each of the plurality of dice forelectrically coupling with at least another one of the plurality of diceand at least one other bus conductor for coupling the redistributioncircuit to the bus conductor; isolating the at least one die contact oneach nonfunctional die of the plurality of dice; testing functional diceof the plurality of dice while integral with the semiconductor wafer;and singulating one of the functional dice of the plurality of dice fromthe semiconductor component.
 13. The method, as recited in claim 12,wherein isolating further comprises probing each of the plurality ofdice to determine the functional dice and the nonfunctional dice of theplurality of dice.
 14. The method, as recited in claim 12, furthercomprising burning-in the semiconductor component while thesemiconductor component is integral with the semiconductor wafer.
 15. Amethod for retrofitting an existing wafer layout for wafer-leveltesting, comprising: on a semiconductor wafer including a plurality ofdice with each die including at least one die contact, forming at leastone wafer-level redistribution circuit on each of the plurality of dicefor interconnection with others of the plurality of dice, the at leastone wafer-level redistribution circuit including a redistributioncircuit for coupling the at least one die contact to a respective bumpedcontact, a bus conductor traversing at least a portion of each of theplurality of dice for electrically coupling with at least another one ofthe plurality of dice, the at least one other bus conductor for couplingthe redistribution circuit to the bus conductor; and isolating at leastone die contact on each nonfunctional die of the plurality of dice. 16.The method, as recited in claim 15, wherein forming further comprisesforming an outer passivation layer over the redistribution circuit andthe bus conductor.
 17. The method, as recited in claim 15, whereinisolating further comprises probing each of the plurality of dice todetermine functional dice and the nonfunctional dice of the plurality ofdice.
 18. The method, as recited in claim 16, wherein isolating includesremoving a portion of the outer passivation layer over the at least onewafer-level redistribution circuit and forming an open circuit betweenthe at least one die contact and the bus conductor on the nonfunctionaldice.
 19. The method, as recited in claim 18, wherein isolating includesablating of at least a portion of the at least one wafer-levelredistribution circuit and the outer passivation layer.
 20. The method,as recited in claim 18, wherein isolating includes etching of at least aportion of the at least one wafer-level redistribution circuit and theouter passivation layer.
 21. A method for isolating nonfunctional dicefrom a wafer-level testing configuration, comprising: forming at leastone wafer-level redistribution circuit on each of a plurality of dicefor interconnection with others of the plurality of dice, the at leastone wafer-level redistribution circuit including a redistributioncircuit for coupling at least one die contact to a respective bumpedcontact, a bus conductor traversing each of the plurality of dice forelectrically coupling with at least another one of the plurality of diceand at least one other bus conductor for coupling the redistributioncircuit to the bus conductor; and isolating the at least one die contacton each nonfunctional die of the plurality of dice.
 22. The method, asrecited in claim 21, further comprising forming an outer passivationlayer over the at least one redistribution circuit and the at least oneother bus conductor.
 23. The method, as recited in claim 22, wherein theouter passivation layer is selectively removable over at least a portionof one of the at least one redistribution circuit and the at least oneother bus conductor for forming an electrical open circuit between theat least one die contact and the at least one other bus conductor when adie of the plurality of dice is determined to be defective.
 24. Themethod, as recited in claim 23, wherein isolating includes etching theat least one redistribution circuit to form the electrical open circuit.25. The method, as recited in claim 23, wherein isolating includesablating the at least one redistribution circuit by a laser to form theelectrical open circuit.